I've ordered a Teensy 4.0 which will arrive in a couple of weeks but am designing a PCB to put it on already.

But I've failed to find anything in the documentation online saying which way up the Program and On/Off pins are - active high or active low. Could somebody let me know as I obviously can't send the PCB off to JLCPCB until I'm sure I have them the right way up.

08-13-2019, 09:15 PM

KurtE

Both signals I believe are setup that if you were to hook them up to a button, you would connect the other side of the button to ground... At least that is how my boards work...

08-13-2019, 09:17 PM

MikeDB

Great thanks. I assumed they would be /Program and /Off but it would have helped if it was documented somewhere.

08-13-2019, 11:28 PM

blackketter

I see that the program pin seems to work as it did in T3.2 and T3.6, but I don't see how to do a system reset with the on/off pin. Is this possible? Or is there another way to do a reset electrically?

08-13-2019, 11:45 PM

MichaelMeissner

Quote:

Originally Posted by blackketter

I see that the program pin seems to work as it did in T3.2 and T3.6, but I don't see how to do a system reset with the on/off pin. Is this possible? Or is there another way to do a reset electrically?

You connect the on/off pin to ground for 4-5 seconds, and the Teensy will turn off. Once you disconnect the Teensy on/off pin from ground and connect it again to ground for 1-2 seconds, the Teensy will turn back on. So it isn't a reset like the 3.5/3.6 had with their reset pin (in the DAC position) or the 3.1/3.2 had with the reset pads underneath the Teensy where connecting the pin to ground would reset it immediately.